Certain embodiments of the present invention generally relate to electrical cable assemblies for use with high speed serial data, and more particularly, to connector assemblies for transferring high speed serial data from a cable to a circuit board.
In the past, cable assemblies have been proposed for connecting electrical cable to circuit boards. Conventional cable assemblies have been provided with an equalizer circuit board within the connector for performing signal conditioning. Performing signal conditioning within a circuit in the connector assembly reduces the time required to incorporate signal conditioning circuit elements with a cable assembly and reduces the time required for connection of the circuit elements with the electrical contacts and the cable conductors. One example of a conventional cable assembly with an equalizer board is described in U.S. Pat. No. 5,766,027, commonly owned with the present application. Conventional high speed serial data connectors (HSSDC) comprise a plug and receptacle combination interconnected through contact fingers. The plug receives an insulated holder that, in turn, receives an equalizer card. The equalizer card includes signal conditioning circuitry.
Both the equalizer card and the data being transferred through the cable are highly susceptible to electromagnetic interference (EMI). Electromagnetic radiation (EM) may be generated by computing and other electronic devices, television, cellular phones, and the like. EMI from one device may interfere with other devices in the surrounding area causing data corruption and/or malfunction of the affected device. Therefore it is advantageous to shield the receptacle and plug to prevent the connector assembly from both interfering with, and being negatively impacted by, other devices that are susceptible to EMI or that generate EM radiation.
Conventional connectors use sheet metal, which either absorbs or reflects electromagnetic radiation, to construct the plug and receptacle. The sheet metal is folded into a desired configuration to form the receptacle. Ground beams, or contacts, are formed integral with the receptacle to provide ground connections with the plug and an external chassis. Traditionally, a single ground plane has been believed to provide the greatest protection from EMI. Therefore, the ground beams have been located to form a single ground plane that is positioned to align with the chassis of a computer, cabinet, external structure, and the like to which the connector is mounted. The ground plane partially surrounds the adjoining surfaces of the receptacle and plug in order to afford EMI shielding around the contact fingers forming the high speed serial data connection between the plug and receptacle. In conventional connectors, a plurality of ground beams are located on the top, bottom and side walls of the receptacle which engage the respective top, bottom and side surfaces of the plug within the single ground plane.
The number of ground beams is limited by the desired size of the receptacle. Therefore, increasing the number of ground beams also increases the complexity at the ground plane location. Additionally, in order to maintain a single ground plane aligned with the chassis, the ground beams have been short by necessity. As a result, one or more ground beams may lose resiliency, or memory, resulting in a poor grounding connection, an increased radiation of EM, and/or an increased susceptibility to EMI.
A need exists for a connector assembly that improves the EMI effectiveness of the receptacle without sacrificing its electrical performance or latching abilities. It is an object of certain embodiments of the present invention to meet these needs and other objectives that will become apparent from the description and drawings set forth below.
In accordance with at least one embodiment, an electrical connector assembly is provided. The electrical connector assembly includes an insulated receptacle housing, an electrical plug, and a ground shield. The insulated receptacle housing holds receptacle contacts within a plug reception chamber in which the electrical plug is accepted. The electrical plug holds plug contacts which engage the receptacle contacts. The ground shield includes top, bottom and side walls that at least partially enclose the insulated receptacle housing. The ground shield has an opening in the front face through which the electrical plug is inserted in the plug reception chamber. First and second sets of ground contacts are formed integral with at least one of the top, bottom and side walls. The first set of ground contacts project inward from at least one of the top, bottom and side walls to form at least one plug contact point with the electrical plug and at least one plug ground plane. The second set of ground contacts project outward from at least one of the top, bottom and side walls to form at least one external contact point with an external ground structure. The second set of ground contacts define at least one external ground plane which differs from the plug ground plane.
In accordance with at least one embodiment, an electrical connector is provided. The electrical connector includes an insulated receptacle housing, a plug member, and a ground shield. The plug member connects to the insulated receptacle housing within a receptacle opening. The plug member holds plug contacts which engage the receptacle contacts held within a receptacle opening of the insulated receptacle housing. The ground shield has top, bottom, side and rear walls which surround the insulated receptacle housing, and an opening in a front face to receive the plug member. Ground contacts are stamped and formed integral with at least one of the top, bottom and side walls. The ground contacts include a first ground contact which extends outward from the ground shield and forms an external contact point with an external ground structure. The external contact point is spaced a first distance from the front face. The ground contacts also include a second ground contact which extends inward from the ground shield and forms a plug contact point with the plug member. The plug contact point is spaced a second distance from the front face which is different from the first distance.
In accordance with at least one embodiment, an electrical connector receptacle is provided. The electrical connector receptacle includes an insulated housing and a conductive ground shield. The insulated housing holds receptacle contacts within a receptacle opening. The conductive ground shield is bent to surround the receptacle housing and has top, bottom, side and rear walls which are formed integral with one another. The shield has an opening in a front face to receive a plug member which has at least one conductive exterior surface. Ground contacts are stamped and formed integral with at least one of the top, bottom and side walls. A first set of ground contacts electrically engages a conductive chassis of a support structure at first contact points which are spaced a first distance from the front face. A second set of ground contacts electrically engages the plug member at second contact points spaced a second distance from the front face.
In accordance with at least one embodiment, an electrical receptacle connector including an insulated housing and a ground shield is provided. The insulated housing has an opening in a front end and an interior chamber holding receptacle contacts having ends which extend from the housing. The opening communicates with the interior chamber and is adapted to receive an electrical plug that engages the receptacle contacts. The ground shield has top, bottom and side walls that at least partially enclose the insulated receptacle housing. The ground shield has an opening in a front face through which the electrical plug is inserted into the interior chamber. First and second sets of ground contacts are formed integral with at least one of the top, bottom and side walls. The first set of ground contacts projects inward from at least one of the top, bottom and side walls forming at least one plug contact point with the electrical plug to define at least one plug ground plane. The second set of ground contacts projects outward from at least one of the top, bottom and side walls forming at least one external contact point with an external ground structure to define at least one external ground plane which is different from the plug ground plane.